Four super absorbent polymers of different component were tested to analyze the effects of them on soil moisture content and growth indices of maize seedlings under drought stress. The result showed that they significant affected soil moisture content, maize seedlings growth and biomass in pot-cultured experiment. Polyacrylic acid-in-organic mineral type（Tangshan Boya） significantly increased soil moisture, biomass of stem, leaf and root of maize,thus it had better water retention effect among four super absorbent polymers. This experiment could provide theoretical basis for choose and application of super absorbent polymers in semiarid region.